Re: [PATCH 01/25] xor: assert that xor_blocks is not called from interrupt context

Christoph Hellwig <[email protected]> Wed, 4 Mar 2026 15:51:34 +0100

Newsgroups	gmane.linux.ports.alpha,gmane.linux.kernel,gmane.linux.ports.arm.kernel,gmane.linux.ports.ppc64.devel,gmane.linux.ports.riscv,gmane.linux.ports.sparc,gmane.linux.uml.devel,gmane.linux.kernel.cryptoapi,gmane.comp.file-systems.btrfs,gmane.linux.kernel.cross-arch,gmane.linux.raid
Message-ID	<[email protected]>

On Tue, Mar 03, 2026 at 11:55:17AM -0800, Eric Biggers wrote:
> may_use_simd() is the "generic" way to check "can the FPU/vector/SIMD
> registers be used".  However, what it does varies by architecture, and
> it's kind of a questionable abstraction in the first place.  It's used
> mostly by architecture-specific code.

Yeah, I don't think that is quite right here.

> How about "WARN_ON_ONCE(!preemptible())"?  I think that covers the union
> of the context restrictions correctly.  (Compared to in_task(), it
> handles the cases where hardirqs or softirqs are disabled.)

Good enough I guess.  Peter?